1. Field of the Invention
This invention relates to rear view mirrors for vehicles, and more particularly to adjustable side-mounted rear view mirrors for automobiles, trucks and the like.
2. Prior Art
To operate an automobile safely, particularly in congested areas and at the high speeds commonly encountered on multi-lane highways, the ability to determine quickly and with certainty whether the adjacent lane is clear to the side and rear before making a lane change is especially important.
Internally mounted rear view mirrors have been developed which widen the driver's vision to the side and rear. However, these devices are normally positioned on or above the windshield, or on the glare shield or instrument panel, near the vehicle's center line, and the roof, roof supports and passenger compartment side walls create dangerous blind spots which can hide nearby or overtaking traffic. The conventional approach to solving this problem is to provide one or more rearwardly facing mirrors on the outside of the vehicle. For convenience these are normally mounted to the front doors near the forward edge of the driver's and front seat passenger's windows.
In most states, statutes restrict the distance objects, such as externally mounted mirrors, may project laterally from the vehicle's side. These statutes, aesthetic considerations, and structural requirements effectively limit the overall width of the exterior side-mounted mirror. This in turn, limits the breadth of the reflected field of vision.
Various side-mounted mirrors have been designed with the specific purpose in mind of providing increased visibility to the sides and rear of the vehicle. Typically these fall into several broad categories. One type employs a laterally curved convex or concave reflective surface, or two or more adjacent reflective surfaces angled with respect to one another, to increase the width of the driver's field of vision. Another utilizes an auxiliary convex reflective surface to augment the view reflected by a conventional plane surface. A third category includes means allowing the driver to change the angular relationship between adjacent reflective surfaces so as to cover selected fields of vision. Yet another type incorporates means for modifying the geometry of the reflective surface itself to enable the driver to vary the field of view.
While some of these prior art devices offer certain advantages, most of them suffer from deficiencies which limit their usefulness, and in some instances render them confusing or misleading to use. None of them is capable of furnishing the driver a reliable, undistorted broad panoramic view extending from the side to the rear of his vehicle.